Which of the following is a correct statement of Newton's first law?
A)An object in motion will continue in motion at a constant speed unless acted on by a net external force.
B)An object at rest will stay at rest unless acted on by a net internal force.
C)An object in motion will continue in motion at a constant velocity unless acted on by a net internal force.
D)An object in motion will continue in motion at a constant velocity unless acted on by a net external force.
E)Everything has inertia.

Question

Quizplus · Accepted Answer

Newton's first law states that an object in motion will remain in motion with a constant velocity (i.e., in a straight line at a constant speed) unless acted upon by a net external force. This law is often referred to as the law of inertia. Option A is close, but it erroneously includes "at a constant speed" instead of "at a constant velocity." Option B refers to net internal forces, which are not relevant to Newton's first law. Option C is also close, but again, it erroneously includes "at a constant speed" instead of "at a constant velocity." Option E is a true statement, but it is not the correct formulation of Newton's first law.

Which of the Following Is a Correct Statement of Newton's